Sudoku
A new unique-solution puzzle every day. Pencil marks, error check, four difficulties.
About Sudoku
Fill the nine-by-nine grid so that every row, every column and every three-by-three box contains the digits one through nine exactly once. Tap a cell, then tap a number or use the keyboard. Notes mode lets you pencil in candidates without committing, and Check highlights any cell that conflicts with the solution.
Every puzzle here has exactly one solution and is solvable by pure logic — no position ever requires a guess. Difficulty changes how deep the required deductions go, not how much guessing is involved. That is a deliberate constraint: a puzzle that forces a coin flip is a broken puzzle.
The daily grid is generated from a shared seed, so every player solves the same puzzle and the daily leaderboard compares solve times on identical work. Solving faster raises your score.
- Players
- 1 player
- Type
- Logic puzzle
- Price
- Free
- Account
- Not required
Sudoku rules
- 1.Fill every row, column, and 3×3 box with the digits 1–9 (no repeats).
- 2.Tap a cell to select it, then tap a number in the pad or press a key.
- 3.Toggle ✏️ Notes to pencil in candidates without committing a digit.
- 4.Press Check to highlight any wrong cells — solve faster for a higher score.
- 5.Each puzzle has a unique solution and never requires guessing.
How to win at Sudoku
- Scan for the forced digit, not the empty cell
- Instead of asking "what goes here", pick a digit and ask where it can possibly go in a given box. Constraint from the three intersecting lines usually leaves exactly one square, and this finds placements far faster than examining cells one by one.
- Pencil marks are for pairs, not for everything
- Noting every candidate in every cell creates a wall of numbers you cannot read. Note candidates only where a cell is down to two or three, which is where the useful patterns live.
- Hunt naked pairs
- When two cells in the same row, column or box both hold exactly the same two candidates, no other cell in that unit can use either digit. Eliminating on that basis usually cascades into several immediate placements.
- Use Check as a tool, not a crutch
- Check tells you a cell is wrong but costs you time and score. Run it when you suspect an error has already poisoned a region, not as a substitute for verifying a placement before you make it.
Sudoku questions
- Does every Sudoku here have a unique solution?
- Yes. Every generated puzzle is verified to have exactly one solution and to be solvable without guessing.
- What does Notes mode do?
- It writes small candidate digits into a cell instead of committing an answer, so you can track possibilities while you reason.
- Is the daily puzzle the same for everyone?
- Yes. All players receive the same grid for a given date, which is what makes the daily leaderboard a fair comparison.
- Do I need an account to play Sudoku?
- No. The puzzle loads and plays without signing in. An account is only required for leaderboard eligibility.
Today's Sudoku challenge
The board above is today's daily: one shared seed, so every player gets the same Sudoku and scores compare fairly. Finish it and your result lands on the daily leaderboard alongside the weekly, monthly and all-time boards.